Launches a privileged utility process.

chrome/utility/chrome_content_utility_client.cc

Index: chrome/utility/chrome_content_utility_client.cc
diff --git a/chrome/utility/chrome_content_utility_client.cc b/chrome/utility/chrome_content_utility_client.cc
index b8f83f05c01132a69070929806b3baef7ea0d665..5298e5711db162a02badf0e82b24a18e348579da 100644
--- a/chrome/utility/chrome_content_utility_client.cc
+++ b/chrome/utility/chrome_content_utility_client.cc
@@ -67,6 +67,11 @@ namespace chrome {
 
 namespace {
 
+// This whitelist is the default list of whitelist entries when running
+// elevated.
+static const uint32 kMessageWhitelist[] = { 0 };
+static const size_t kMessageWhitelistSize = arraysize(kMessageWhitelist);
+
 bool Send(IPC::Message* message) {
   return content::UtilityThread::Get()->Send(message);
 }
@@ -77,7 +82,8 @@ void ReleaseProcessIfNeeded() {
 
 }  // namespace
 
-ChromeContentUtilityClient::ChromeContentUtilityClient() {
+ChromeContentUtilityClient::ChromeContentUtilityClient()
+    : filter_messages_(false) {
 #if !defined(OS_ANDROID)
   handlers_.push_back(new ProfileImportHandler());
 #endif  // OS_ANDROID
@@ -109,10 +115,26 @@ void ChromeContentUtilityClient::UtilityThreadStarted() {
   std::string lang = command_line->GetSwitchValueASCII(switches::kLang);
   if (!lang.empty())
     extension_l10n_util::SetProcessLocale(lang);
+
+  if (command_line->HasSwitch(switches::kUtilityProcessRunningElevated)) {
+    DVLOG(0) << "Utility process is running elevated, restricting messages.";
+    for (size_t i = 0; i < kMessageWhitelistSize; i++) {
+      message_id_whitelist_.insert(kMessageWhitelist[i]);
+    }
+    filter_messages_ = true;
+  }
 }
 
 bool ChromeContentUtilityClient::OnMessageReceived(
     const IPC::Message& message) {
+  if (filter_messages_
+      && message_id_whitelist_.find(message.type())
+         == message_id_whitelist_.end()) {
+    DVLOG(0) << "Message rejected, not in whitelist: "
+             << message.type();
+    return false;
+  }
+
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(ChromeContentUtilityClient, message)
     IPC_MESSAGE_HANDLER(ChromeUtilityMsg_UnpackExtension, OnUnpackExtension)
@@ -179,6 +201,14 @@ void ChromeContentUtilityClient::PreSandboxStartup() {
     media::InitializeMediaLibrary(media_path);
 }
 
+void ChromeContentUtilityClient::AddHandler(UtilityMessageHandler* handler) {
+  handlers_.push_back(handler);
+}
+
+void ChromeContentUtilityClient::AddWhitelistMessageType(int message_type) {
+  message_id_whitelist_.insert(message_type);
+}
+
 void ChromeContentUtilityClient::OnUnpackExtension(
     const base::FilePath& extension_path,
     const std::string& extension_id,